The phenotypic characteristics of the donor mean: eye colour, hair colour, tone of the skin, body build, for example, how tall they are, what is their weight, are they medium build, light build or heavy build. Usually phenotypic characteristics are tried to match with phenotypic characteristics with intended parents.
We are talking about, for example, donor programs. Patients will choose a donor who has the same phenotype as them so that the baby will look like his parents. If we’re talking about babies after IVF; they are the same, they are naturally conceived so they have no special phenotype characteristics.
Phenotypic characteristics are those traits, physical, biochemical and behavioral that are obvious when you look at a person, they are observable and measurable. Moreover, these characteristics are the expression of the genetic traits that each of us has in an observable way. It is important to highlight that some of them can be influenced by environmental factors and lifestyle like diet, exercise and the consumption of tobacco or alcohol.
One of the most common examples, to understand this concept, is the color of the eyes. We inherit the genes from our ancestors related to this characteristic and even though it is defined in our genes, in our genotype it is a trait that we can observe.
And how it is related to assisted reproduction? Well, these characteristics are very important when we talk about donors and recipients. As you may know, the donation of oocytes and sperm is a very common option when the quality or the quantity of the patient’s eggs or sperm is an obstacle in the way of a successful pregnancy and also if there is a multiple hereditary genetic disorder identified as high.
The selection of donors is a very important process and we try to look for the maximum phenotype compatibility when we have to choose a donor. However, we always have to take into account that it is impossible to guarantee that these characteristics will be on the offspring.
On one hand, that is important in order to find a donor physically similar to the recipient with the consequent effect in the offspring phenotype. So even if the woman or the man are not the biological parents of the baby, it can be physically similar to them. However, can’t forget that our phenotypic traits are closely related with the genotype, with our gene pool. Therefore, it is obvious to think that if we are, genetically speaking, more compatible with the donor, there are more probabilities to have a compatible genotype and a better response of the recipient as well as more probabilities to get pregnant and to have a healthy baby.
Phenotypic means everything that can be seen or measured for example weight of the person, the height, eyes colour, hair colour, blood type or so on. It is different when we consider genotype or genotypic characteristics. Genotypic is genetic coding of information and expression of that information that we can see is what we call phenotypic characteristics.
We can differentiate between two different types of features: genetic (genotype) and physical (phenotype). Regarding the genetic type, it can be measured in the lab. They could be taken into account when choosing a donor, using a karyotype test. The physical characteristics of a person is called phenotype and it involves eye colour, hair colour, ethnicity, hair type, body type, etc., anything that you can see in a photo and use to compare a person to another person. The embryologists and doctors usually measure these phenotypic issues (like hair colour, eye colour) with different donors so they can get the biggest similarity to the patient. Fenomatch measures this kind of features based on photos of the donor and patient and gives scientific arguments for the decision to choose the donor.
